Get a Pentest and security assessment of your IT network.

Cyber Security

Mobile Phone Calls Without Signal

TL;DR

You can make calls from your mobile phone without a cellular signal using Wi-Fi calling, VoIP apps (like WhatsApp, Skype, or Messenger), satellite phones, and in emergencies, emergency SMS. Each method has different requirements and costs.

Making Calls Without Cellular Signal

  1. Wi-Fi Calling
    • How it works: Wi-Fi calling uses a Wi-Fi network instead of the mobile network to make and receive calls. Your phone number stays the same.
    • Requirements: A smartphone with Wi-Fi calling support, a stable Wi-Fi connection, and your mobile provider must support Wi-Fi calling (check their website).
    • Setup: Usually enabled in your phone’s settings. Go to Settings > Network & Internet > Mobile network and look for ‘Wi-Fi Calling’. Turn it on. You may need to verify your address.
  2. VoIP Apps (Voice over Internet Protocol)
    • How it works: These apps use the internet to make calls. Examples include WhatsApp, Skype, Messenger, Viber, and Google Voice.
    • Requirements: A smartphone, a stable Wi-Fi or data connection, and an account with the VoIP app. The person you’re calling also needs the same app (or for some apps, you can call regular phone numbers for a fee).
    • Setup: Download and install the app, create an account, and grant it permission to access your microphone and contacts.
    • Example (WhatsApp): Open WhatsApp, tap the phone icon in the contact’s chat, and select ‘Voice Call’.
  3. Satellite Phones
    • How it works: Satellite phones connect directly to satellites instead of cell towers. They work almost anywhere on Earth.
    • Requirements: A satellite phone (expensive!), a clear view of the sky, and an active subscription with a satellite provider.
    • Cost: Phones cost hundreds or thousands of pounds. Call costs are also high – typically several pounds per minute.
  4. Emergency SMS (Text Only)
    • How it works: Even without signal, you can sometimes send emergency text messages to 999 or 112. This uses any available network, even if your provider doesn’t normally work in that area.
    • Requirements: A smartphone and a clear view of the sky (may help). This is not guaranteed to work everywhere.
    • Important: Only use this for genuine emergencies. It may take longer for emergency services to respond via text than by voice call.

Troubleshooting

  1. Wi-Fi Calling Not Working?
    • Check your Wi-Fi connection is strong and stable.
    • Restart your phone.
    • Make sure Wi-Fi calling is enabled in settings (as above).
    • Contact your mobile provider to confirm they support Wi-Fi calling on your device and plan.
  2. VoIP App Issues?
    • Check your internet connection.
    • Update the app to the latest version.
    • Ensure the app has permission to access your microphone.
Related posts
Cyber Security

Zip Codes & PII: Are They Personal Data?

Cyber Security

Zero-Day Vulnerabilities: User Defence Guide

Cyber Security

Zero Knowledge Voting with Trusted Server

Cyber Security

ZeroNet: 51% Attack Risks & Mitigation